I went with MicroZOTL L2 Pre. I am keeping it. Never tried Backert but I am sure it won't disappoint either. I did a quick review on MicroZOTL in another thread.
@benzman - not sure which version of the microzotl pre you had, but mine has - 15db and - 30db gain adjustments. Sweet spot for me is the 15db gain setting. With that I can bring the volume up o 50 out of 99 no problem. I sit about 7 ft away from the speakers and listen at about 55 to 65 db.